1. Field of the Invention
This invention pertains to electrical power supplies, and more particularly to apparatus for providing auxiliary electric power to motor vehicles.
2. Description of the Prior Art
Many modern automobiles and other motor vehicles are equipped with electrically powered and computer controlled accessories, such as clocks and radios. The accessories usually receive their operating power from the vehicle storage battery. Under normal conditions, the accessories operate continuously and reliably without attention from the vehicle owner.
Occasionally, however, the vehicle must be serviced in a manner that requires disconnection of the storage battery. In those situations, electric power to the vehicle accessories is lost. As a consequence, the programmed memory of the on-board computer that controls the clock, radio, door locks, and other accessories is also lost. After restoration of the power from the vehicle battery, the service man must reset the clock, radio, and other computer controlled accessories. Such resettings are undesirable, because of the increased expense to the owner. In addition, after storage battery disconnection and reconnection, it may take up to 200 miles of driving to reprogram some computer functions.
Thus, a need exists for maintaining electrical power to certain vehicle accessories when normal vehicle power is interrupted.